This invention relates to non-contact optical gauging apparatus, and more particularly to such apparatus for accurate measurement of diameter or other linear dimensions.
Many devices are available for such purposes, but the device here disclosed possesses a combination of several advantages seemingly absent from other available devices. These advantages include absence of the need for contact with the object being measured, permanent calibration, capacity for high measurement rate, simplicity of construction and relatively low cost. Of particular importance are relative independence of the position of the object in the measurement field, and of regular or random movement during measurement. Moreover, the device is capable of high resolution, and of accuracy comparable to the resolution.